Answers for light and sound review
1. Low amplitude/high frequency = quiet, high pitch, like a flute. High amplitude/low frequency = loud, low sound – like a tuba
2. A. 6steps/4seconds = 1.5 steps/second (frequency) b. 1.4m/5waves = .28m (wavelength) 7 m/10 sec = 0.7 m/s
3. A. shake less often, b. shake more vigorously c. shake more often, d. shake less often, e. change the spring
4. V = f*wavelength à wavelength = 0.77m
5. V = 1428m/s, wavelength = 3.24m, f = 440 Hz (same…. Frequency doesn’t change)
6. UV has higher frequency = more energy = more dangerous
7. V = f*wavelength à3.25m
8. F = 4.29x1014 Hz, v = 2.3x108 m/s, wavelength = 5.38x10-7 m
9. Bright red vs dim blue
Here's where you can vote if the frame below doesn't load....
Light HW #1 - hints
1. Start by converting 98.8MEGAhertz into simple Hertz. Use the wave equation to solve for wavelength. Google what values the different parts of the EM spectrum have. wavelength = 3.04m, that's FM radio
2. When we listed all the EM waves in the spectrum, what defining characteristic described how damaging (or energetic) each type was? Could you calculate it using the wave equation? shorter wavelength = higher frequency = more dangerous. One is microwaves one is x-rays (more dangerous)
3. Ignore the car. How many meters can light go in one second? How many times farther is that distance than 76251? 3934.4 times
4. What is the ratio of light speed to sound speed? Are you expecting a big number or a small number? Mach 882352 (fast...)
5.Turn 150million KILOmeters into meters... then use v = d/t. t = 500 seconds (8 minutes 20 seconds)
6. Similar to #5 t = 255 seconds (4 minutes 15 seconds)
7. These are in your notes...
8. Same as #7...
4.4 - Coulomb's law puzzle - Why did the electron have so few friends? WS Due at beginning of class Thursday, 2-28 (I'll be checking your calculations, not the solution to the puzzle - that's just to let you know if you're doing it right)
4.2c - hand drawn WS of ONE circuit with 4 bulbs and 4 batteries. Use a VIRP table (and maybe the simulator to check your answer?) Due T 2-9-13.
4.2 - Hand drawn WS over circuits with resistors in series. Use a VIRP table to help analyze the circuit. Due F 2-08-13.
4.1a - WS over circuits with multiple batteries. Completion grade, corrected in class, due W 2-6-2013.
4.1 - WS over Ohm's law. Completion grade, corrected in class, due F 2-1-2013.
Here's the document I gave out in class on April 29th
Electric House Project
UPDATED RULES: (as of W 2-27-2013)
Your design must:
- have at least two rooms (three if you're working with a partner)
- have all wires hidden (your room at home shouldn't have cables and wires running all over the floor)
- Use battery power, not AC power (9V, D, C, AA, or AAA)
- FOR THE BONUS POINTS - you must clear your idea with me by next Friday 3-7-2013
DC Series Circuit Challenge
1) Make a light bulb light brightly using 4 batteries.
2) Add an on/off switch.
3) Make 3 light bulbs light brightly with all 3 with the same brightness (same current, measures the same number of amps).
4) have all 3 bulbs on, and have a switch that turns on/off 2 of the 3.
5) Have a switch that turns on/off all 3 lights at once.
6) Make a circuit with one main on/off switch that will turn on/off 3 bulbs, each with a different brightness. Use the non-contact Ammeter to check for different currents.
7) Change the circuit so 1 switch will turn on/off all the lights
and a second switch will change the lights from all being the same brightness to all being different brightnesses.